lastb failed on opensuse 11.1

The lastb command does not show any login failure on version 11.1.
I created the file /var/log/btmp with access rights 600 for root:root. In the file /etc/login.defs there was in older versions a line
FTMP_FILE /var/log/btmp
This line is not longer in login.defs. The man page for login.defs even does not show anymore the option FTMP_File.
Do you know how i can get invalid login stored in the btmp file.
Any help are welcome

Additional information:
The invalid login is not logged in btmp if the login fails on local terminals.
ssh login errors are logged correct.